Retubing a TriAxis a 2:90

[Timbre Wolf]

Glad you’ve jumped in here, Rob. Yes, I’m still “evangelizing,” mostly because I can’t contain my enthusiasm on this topic. Sorry to hear your Triaxis is still acting up, mate. Gotta get over that soon!

Hey, you know, your comment about enjoying GAIN got me thinking that I do too, for certain situations. I think I may have misrepresented the advantages of some tube choices, particularly the Mullard CV4024. You can have this lower-mu valve in the input and still get nice singing, fluid, high gain out of both Lead 1 and Lead 2. The key difference is that it is easier to get cleaner rhythm/clean mode settings, and the clean-to-overdriven range in the lead modes is broader. Honestly, I don’t think you could get a better smooth, creamy, and soaring sound out of the Triaxis than in Lead 2 Green, with a Mullard CV4024 in V2 and a long plate/halo-getter Mullard ECC83 in V4: it is pure, joyous, heaven! Doesn’t matter what style music you play. Cranking a nice power amp (I love my Mesa 20/20 with Tungsram EL84s) through AlNiCo speakers (I run stereo through two Mesa wide-body 1x12’s with a Weber Blue Dog in one and a Silver Bell in the other) helps too, by the way.

I’m going to make some concluding remarks about this tube-tasting foolishness, and then I’ll get off my soapbox. I would like to suggest changing the phrase “trial and error” to “trial and success,” because I’ve really improved my own satisfaction level during this process. I thoroughly love how my Triaxis-20/20 system has gained character, expressiveness, tone and feel (my rack system now feels as responsive as an integrated combo amp, but is infinitely more variable), and that inspires me to be a better player. Here are my main discoveries:
1) Subjectivity rules - only you know what you like, and there is no objective "best" tube; only a cast of characters.
2) Tubes favored in one amp/preamp are often not favored in another amp/preamp. This also goes for different players.
3) Combinations of tubes in a circuit bring in a complexity that may cause you to favor different tubes than you would expect if you simply considered each valve separately.
4) It really helps to have a variety of choices with which to experiment. Warning: this may be expensive!!
5) Wow – it’s FUN!

Summary of Triaxis Tube Choices (for my little piece of sonic nirvana):
V1 Raytheon long black plate, halo-getter12AX7
V2 Mullard CV4024/12AT7WA (654 type, ’70’s-‘80’s production)
V3 RCA 5751 black plate/3-mica
V4 Mullard long plate/halo getter ECC83 (f91 and f92 types, late ‘50’s production)
V5 RCA black plate 12BZ7

Rock on, y’all…
- T

 

[frednerk_30]

G'day T

I think we need to get you deliberations up on a web site somewhere.
You have too much knowledge to leave it just hanging around in the nebulous and fragmented forum space. I'll host it if you want. Let me know.

I think I'll need to talk to you about speakers again in the not too distant future. I'm still thinking Weber speakers. But that's another story.

Oh, by the way, I just got a JJ803s long plate this morning. I try it out tonight and post my impressions here. A lot of people say this particular tube has nice thick mids. I'm very keen to check this current production tube out now that I have the Mullard as bench mark. I also got a complete set of JJ6L6's and JJ83s to retube my 2:90. I expect it will be a vast improvement over the OLD Chinese junk that's in there at the moment. Here's hoping.

Have a fantastic day
-R

 

[Timbre Wolf]

I'd really like to hear your impressions of the JJ803s, Fred. :wink: Perhaps with some comparisons to the standard JJ version, and any others you have.

I really have little to say about current-production tubes because, for the most part, I have not tried them. Actually, that is not entirely true; I have tried Sovteks and Mesa-branded Chinese 12AX7s, and I did not mention them in my review because my opinion would have read much like my take on the Sovetek 5751 (harsh opinion for harsh tubes?).

I have tried Electro Harmonix's 12AX7EH, and, despite my strong disagreement with a recent (March 2005) Guitar Player magazine review (where this tube was described as "exceptionally balanced and even response from top to bottom...top-end is tastefully extended without sounding harsh, brittle, or nasty, and its bottom and midrange are deep and full with a rich thickness that is detailed, layered, and complex), I do appreciate that their character (hint of nasal high-mid; crisp biting highs; low-mid lacking) could appeal to some folks who need to bring a dark-sounding circuit to life, even if it is in a rather crude way. Well, I am strongly opinionated, but if you think this tube is rich, detailed, and complex, then you're in for a real treat with many of the NOS goodies I've tried.

Another current-production tube I have appreciated is the Ei 12AX7. Before I knew it was modeled after the Telefunken smooth plate ECC83, I noted it had a reminiscent character. There were airy and pleasant highs and clarity, but, like the Telefunken, it seemed to have a somewhat sterile response, so I removed it (before I could confirm that they typically go microphonic after low hours of use).

Well, to stick to the main topic McManus raised, I think we should discuss the Weber speakers in a different thread. I do like your idea of putting together a web page for the Triaxis tube information. I was thinking, as I was writing it, that it could be useful to have photos of some of these NOS tubes - when you're trying to identify something that was made for only a short time over 40 years ago, any further assurance can be helpful before you dish out the green. Let's see what we can do.

Before I forget, here's a site where some very knowledgeable (and obsessed) folks have discussed tubes from a hi-fi perspective. Although the needs and applications are different (well, there are some guitar players there), I have found it useful to search for a particular tubes' descriptions as a reality check: http://www.audioasylum.com/audio/tubes/bbs.html

Fantastic Day right back to ya!

 

[frednerk_30]

Ok, I tried out the JJ803s over the last couple of days.

Comparison is between Mullard 12AT7WA (M8162/CV4024) and JJ ECC803s (apples and oranges anyone?) in Pos 2 of Triaxis. Guitar is Zion (strat stlye guitar) with Seymour Duncan JB (full humbucker) in bridge.
Power amp is simul 2:90.

Mullard

• Hghs are more transparent, sweeter and refined. No nasty spike here. I never feel like there are lumps or dips from high mids through high treble that I need to "correct". If I want more treble, I just adjust the control and it's all there, all. It's about tonal balance not tonal correction if you get my drift.
  Has more and rounder lower mids.
  Gain can be lowered and this tube retains mids quite well.
  Attack envelope seems more precise and refined.
  Although quite compressed offers more variation in gain under varied picking dynamics.
  Lows are warmer.

JJ803s

• More upper mids and also a little more crunchy in this region.
  Highs are more rebellious and don't blossom like the Mullard.
  Seems more compressed and the tone retains is character under
  varying pick dynamics. Tonally stiffer.

Both tubes have a decent amount of mids which I prefer. It's much easier to dial out mids than get them there in the first place in my opinion. Although I prefer the Mullard for what I want to achieve, the JJ803s is certainly a welcome addition to the current production tubes and I am certainly glad to have it in my kit. You see, I am new to this tube experimentation thing and am simply amazed how much of a difference they make. There are so many variables within a guitarist's amplification system (pickups, string gauge and type, speakers, etc) that one really needs to experiment (a lot) to discover the combination that "floats your boat". Go for it and let us know what you think.

PS - Because of it's stiffer character the JJ seems to do a nice job of clarifying LD 1 modes.

 

[mcmanus]

Sorry I've been out of the loop a bit... family's been visiting, which means not much playing, heh...

Well, I went ahead and started out with JJ's (don't worry, there'll be plenty more variety coming my way in the future). I figured they were a good place to start. I got a full set of ECC83S for the TriAxis (high gain tubes for V1, V2, and V4, and balanced for V5), and I got an octet of 6L6GC's for the SimulClass.

Just a note before I start my opinion, I just want to say that I still suspect that my 2:90 has problems (I swear I only get half the drive out of it that I'm supposed to), that I'm still trying to get resolved with Mesa/Boogie (more on that later), so things my change when I get it completely fixed.

Anyhoo... I found that the JJ's were excessively bright in the TriAxis, and that mids and bass were nowhere to be found, no matter how I dialed it in. I'm not sure if they're bad tubes, or this is just a side effect of the "high gain" tubes, but to be honest it sounded a lot better when I swapped the stock Russian (yeah, no more Chinese in the new TriAxis) 12AX7's back in! I may have to call Bob up and see what he says about it.

However, I am quite happy with the JJ 6L6GC's in the SimulClass 2:90. They complement the harshness of the stock Russian 12AX7's in the TriAxis quite nicely! They give it a slightly smoother and more well rounded sound, and just the tiniest bit warmer (due to the "hotter grade", whatever that means). Not bad... I'm quite happy with them.

So thumbs up on the JJ 6L6GC'S, thumbs down on the JJ 12AX7's (we'll see if Bob will let me switch them out for the "normal" ones). Next up on my list to try is: SED Winged C's for the 2:90, and the Mullard 12AT7's in the TriAxis.

Quick question about the Mullard 12AT7's... Would you all recommend getting 5 for the TriAxis, or just putting them into the V1, V2, and V4 positions? And how much "less gain" are we talking here? It may (or may not) be a problem with my 2:90 as it is right now, seeing as how I'm pressed for gain, but I'm definitely willing to try it. How many do you recommend I get for now?

 

[frednerk_30]

I'm using just one Mullard 12at7 in pos 2.
I haven't tried it elsewhere yet.
Having just one in this position does wonders.

 

[Timbre Wolf]

FredNerk - thanks for the Mullard 12AT7/CV4024 <-> JJ803S comparison. I guess this means your Triaxis is back up and running: congratulations! I think you hit the nail on the head about the CV4024 having a more "transparent" capacity for highs: highs are available, but they don't jump out and poke at you. I wonder how the JJ803S would behave in combination with the CV4024, if you had the 803S in V1 and the CV4024 in V2?

McManus - I don't recommend loading up all five positions with the CV4024, for a couple of reasons. For the lead modes, I think this tube works best in combination with a 12AX7 (so 12AX7 in V1 and V4). Because the CV4024 doesn't assert high frequencies, I find that, in the lead modes, it is best to combine it with a different tube that does assert these frequencies more (but not as much as some buzzy current-production tubes). You might consider the CV4024 for V3, as I've found it very nice in this mixer position, but definitely put a 12AX7 in V5, for a higher gain output.

This whole topic is very complicated. As FredNerk said, when it comes to electric guitar, there are many tonal factors in the pathway between your fingers and your ears. For instance, if you want a cheap thrill, try a radically different thickness of pick - I went from a 1.0mm to a 0.60mm pick and was astounded at the tonal difference. But don't worry, I won't get us started on NOS nitrocellulose plectra from the 1950's :lol: Back to tubes: I find it best to arrange combinations with tubes that have distinct character (my boat is floating on this concept).

I have a question for you both, since you own 2:90 amps: where are the 12AX7 tubes located? Are they inside, so you have to remove screws to get to them? It has been too long since I sold mine, and I can't remember. My real question is if there is enough room for the 12BZ7 input tube (about 7/16" taller than 12AX7), because I highly recommend these inexpensive (less than $10) tubes for creating a more lively rig.

 

[Timbre Wolf]

Oops! I just read your p.s., FredNerk, and now my suggestion for trying the JJ803S in V1 doesn't seem very profound - you're already doing it!

I had another thought on the JJ803S: I have heard descriptions of preamp tubes changing after 50-100 hours of "break-in" time (highs become more pleasant and slightly less edgy, and they become less stiff). I wonder if this might happen with this tube. Keep us posted. I have encountered tubes with a stiffer response/feel (such as the JAN-GE 12AX7WA), and I have not run them long enough to see if they break in to a more relaxed demeanor.

 

[mcmanus]

Thanks for the info TimbreWolf... I'll go try out a Mullard 12AT7A ASAP. I'll prolly grab 2 and try it in the V3 as well.

As far as the 2:90 goes, I _think_ it's inside. You definitely can't see it anywhere on the outside, heh. I have 3 "normal" JJ 12AX7's that I need to put in, but I might just have my local amp tech do it when I have him try to fix the gain issue, heh. I'm lazy.

 

[frednerk_30]

The 2:90 has three 12ax7 inside. They stand upright.
A couple of screws later and you in!
Just don't touch anything except the tubes.

Hey mcmanus (c++), let us know what you think of the
Mullard 12AT7WA (M8162/CV4024). Reality check for myself.


I think I will have to acquire a little stash of Mullard 12AT7WA
in the very near future.

Timbre Wolf - my Triaxis mysteriously got better all by itself but
for how long! The problem I was having was that over about 10
minutes (in LD11) the gain would decrease, treble would become
more prominent, and mids would disappear. Also a hissing noise
that the noise-gate could not get rid of developed. So I took the lid off
and the problem disappeared. Go figure. So I put the lid back on
and it's been behaving itself for the last 4 or 5 days. I think I have
a very naughty and wilful Triaxis that needs a **** good .... ouch.

In relation to your comment about the 12BZ7 you mention "more lively".
Does "more lively" mean less compressed, more dynamic?

THE NERK

 

[mcmanus]

The 2:90 has three 12ax7 inside. They stand upright.
A couple of screws later and you in!
Just don't touch anything except the tubes.

Hey mcmanus (c++), let us know what you think of the
Mullard 12AT7WA (M8162/CV4024). Reality check for myself.


I think I will have to acquire a little stash of Mullard 12AT7WA
in the very near future.

Timbre Wolf - my Triaxis mysteriously got better all by itself but
for how long! The problem I was having was that over about 10
minutes (in LD11) the gain would decrease, treble would become
more prominent, and mids would disappear. Also a hissing noise
that the noise-gate could not get rid of developed. So I took the lid off
and the problem disappeared. Go figure. So I put the lid back on
and it's been behaving itself for the last 4 or 5 days. I think I have
a very naughty and wilful Triaxis that needs a **** good .... ouch.

In relation to your comment about the 12BZ7 you mention "more lively".
Does "more lively" mean less compressed, more dynamic?

THE NERK

frednerk, with the exception of the hissing, that actually sounds just like what I'm experiencing with my 2:90 ! My local amp tech is going to look into it for me after he finished doing the bias mod on my 5150. Are you sure it's the TriAxis and not the 2:90 doing it?

 

[frednerk_30]

G'day mcmanus

I'm pretty certain it's the Triaxis. Maybe there is a combination
thing going on. I noticed that when the Triaxis got thin (and I mean very thin) simply unplugging the signal cable between the Triaxis and the 2:90 restored all the mids. Then over about 5 minutes... thin again.
The same thing would happen if I just change patches and then back again.

See if you can get a nice comprehensive technical explanation of why your gear is malfunctioning from you tech when you get it sorted out,
in writing if at all possible. I'd really like to know.

My Triaxis has been driving me nuts. Although it has been very nice to me for last couple of days.

 

[Timbre Wolf]

In relation to your comment about the 12BZ7 you mention "more lively".
Does "more lively" mean less compressed, more dynamic?

Yes, the 12BZ7 makes the Triaxis more dynamic (which improves a common complaint about this preamp: too compressed). This is a feel aspect, not a tonal one. This tube makes your signal louder (= more gain, but the same mu of 100, which means that the signal is no more distorted than a standard 12AX7). So a small change in picking dynamics is amplified over a broader range of amplitude. Set your power amp on the edge of breakup and you can ride that edge more easily with the 12BZ7, especially if you use one in the power amp input position as well as Triaxis V5/output. Of course, because of the somewhat-lower volume level of my 20/20, the power amp breakup is easier on a naked ear than with the 2:90 that you and McManus use. I love making my Tungsram EL84s sweat a little - it brings out the best in them.

Wish I could offer you chaps some winning advice on getting the gear to operate. Mr. Nerk, the problem you're having in Lead 2 sounds like the only problem (tubes aside) I've ever had with my Triaxis. It only happened in Lead 2, no other mode, and it was independent of the tube in V4. Eventually that mode stopped working. The good folks at M/B fixed it right up, but I didn't find out exactly what the problem was. Perhaps there's a weakness in the Triaxis at some point in the Lead 2 circuit? Contact Mesa/Boogie and see if they'll help you locate this problem. If it helps, I'll look up my repair date ('round September/October of last year) info, and perhaps they've retained a record of work done?

 

[frednerk_30]

Thanks for the info Mr. Wolf.
Yes my Triaxis only seems to have this problem in LD11 as well.
I did actually give the preamp to the local techs for repair.
These guys are the importers/retailers/repairers for Mesa/Boogie in Australia. They couldn't find a problem! They suggested I might like to ship the unit back to the United States to get it looked at. I don't particularly want to spend $800 (guesstimate) and be without it for months on end though. They also suggested I just sell it and get another one. Hmmm. Believe me, I could say a whole lot more ...

I'll probably take you advice Mr. Wolf and get in contact with Mesa/Boogie and see what they can do to help.

 

[mcmanus]

Michael's a good guy, but his only advice to me was take it to a good (m/b authorized) local tech. He gave me the name of a very reputable tech here in Austin that he personally trusts. Don't know if he can say the same about Australia.

I say sell it! I returned my original TriAxis (gain problems, but in Lead 1 mostly), and I'm going to return my "clearance item" 2:90 (thank you Guitar Center, ugh), and get a new one from a local store.

 

[MesieBooga]

For the past three years I have been delving deeply in 12AX7 tube substitutions in my Triaxis -> 20/20 rig, and I can probably help you. I have experimented extensively with more than 30 variants (mostly NOS).

First, though, please tell me which modes you gravitate towards, and what you'd like to accomplish (i.e. more/less compressed, articulate, overdriven, bass/mid/treble, dynamic, etc.)? Your budget and patience levels are also important factors, but if you're obsessed like me, you'll probably find a way to navigate those obstacles successively.

Do you like the 20/20 better than the 2:90 for the Triaxis?

 

[Timbre Wolf]

For the past three years I have been delving deeply in 12AX7 tube substitutions in my Triaxis -> 20/20 rig, and I can probably help you. I have experimented extensively with more than 30 variants (mostly NOS).

First, though, please tell me which modes you gravitate towards, and what you'd like to accomplish (i.e. more/less compressed, articulate, overdriven, bass/mid/treble, dynamic, etc.)? Your budget and patience levels are also important factors, but if you're obsessed like me, you'll probably find a way to navigate those obstacles successfully.(I edited this to read as I intended

Do you like the 20/20 better than the 2:90 for the Triaxis?

Short answer: yes

Medium answer: they both have their places, and I'd still use the 2:90 if I needed it. I no longer do the larger gigs, though (I'm being a dad these days), so I don't need the higher wattage. I prefer lower wattage for studio and small gigs. I never really got to open up the 2:90 and take full advantage of the power it had, so I'd probably go with the 50/50 (from M/B choices) for those larger gigs.

The 20/20 is great when cranked, especially if you've got some good tubes in there. I love how my Tungsram EL84 bring out the best (well, maybe it'd be better with '50s Amperex EL84?) in the amp. It is loud, but I can get decent power tube breakup without blowing out the windows.

Long answer: you don't really want the long answer. 8)

- T

 

[MesieBooga]

For the past three years I have been delving deeply in 12AX7 tube substitutions in my Triaxis -> 20/20 rig, and I can probably help you. I have experimented extensively with more than 30 variants (mostly NOS).

First, though, please tell me which modes you gravitate towards, and what you'd like to accomplish (i.e. more/less compressed, articulate, overdriven, bass/mid/treble, dynamic, etc.)? Your budget and patience levels are also important factors, but if you're obsessed like me, you'll probably find a way to navigate those obstacles successfully.(I edited this to read as I intended

Do you like the 20/20 better than the 2:90 for the Triaxis?

Short answer: yes

Medium answer: they both have their places, and I'd still use the 2:90 if I needed it. I no longer do the larger gigs, though (I'm being a dad these days), so I don't need the higher wattage. I prefer lower wattage for studio and small gigs. I never really got to open up the 2:90 and take full advantage of the power it had, so I'd probably go with the 50/50 (from M/B choices) for those larger gigs.

The 20/20 is great when cranked, especially if you've got some good tubes in there. I love how my Tungsram EL84 bring out the best (well, maybe it'd be better with '50s Amperex EL84?) in the amp. It is loud, but I can get decent power tube breakup without blowing out the windows.

Long answer: you don't really want the long answer. 8)

- T

I used to use a 20/20 with a JMP-1 and it was the bomb. Now I have another Triaxis on the way and was thinking about a 20/20 or a 2:90.
Can't you just run the 2:90 lower volumes too? And do you really mean CRANK the 20/20? :shock: (I know the volume can be adjusted on the preamp too)

 

[Timbre Wolf]

There's a difference, in feel and sound, between a small-wattage amp running so the power tubes are breaking up, and a higher-wattage amp thats been turned down to the same dB output as the first rig. In a power section that's starting to sweat, there is a compression effect that you don't get from the larger amp. Of course, with the larger power amp, you'll get a stronger capacity for low-frequency response, too, so there are multiple factors going on at once.

Generally, it is best to change amps to suit a venue size: smaller venue = smaller amp, so you can get your power section running at high enough volume to get it to work optimally with your preamp.

do you really mean CRANK the 20/20?

Yes. Well, the actual volume knob doesn't need to be turned fully clockwise for this. In fact, there's not much difference between the 12:00 position, and the 5:00 position. But the point is to get the power section to begin breaking up. Yes, it is LOUD!

- T

 

[MesieBooga]

Thanks I guess I knew that.
I've never owned a 2:90 but the EL84 20/20 is great despite the lack of low end.
I will try to run the Triaxis thru my IIC+ and Diezel prior to getting a power amp anyway.
p.s. U ROCK!